You may not think that those small cracks and crevices around your doors and windows  are a very big deal. But, did you know that a 1/8" space between a standard  exterior door and its threshold is equivalent to a two square inch hole  in the wall?

Closing those gaps can save you up to 15 percent in heating  and cooling costs and also can reduce the demand on your heating and cooling  system. Best of all, you can probably weatherstrip your entire home in  a single day.